Aptevo Therapeutics Stock Is Sinking Today - Here's Why

Aptevo Therapeutics Inc APVO announced that its bispecific acute myelogenous leukemia (AML) drug candidate APVO436, in combination with venetoclax and azacitidine, achieved positive duration of remission results in its Phase 1b dose-escalation trial. 

High response rate observed: 82% (9/11) of patients had a favorable response and were eligible for inclusion in the Duration of Remission (DOR) analysis.

3/11 patients responded sufficiently to move to stem cell transplant - receiving a stem cell transplant is the treatment option.

Related: Aptevo Stock Jumps As Acute Myeloid Leukemia Combo Therapy Achieves 100% Clinical Benefit Rate.

Of the patients with responses, one patient remained on the study with a sustained complete response for 8 cycles (the maximum allowed per protocol), translating into at least 8 months of response duration.

The median DOR was not reached, which is clinically meaningful because a substantial number of patients either stayed on treatment or moved to transplant and did not experience a relapse event.

The company is also providing an update of its APVO436 Phase 2 program design that will include frontline and relapsed/refractory trials beginning in the second half of 2023.

The company's APVO436 Phase 2 program will further evaluate the triplet combination of APVO436 + venetoclax + azacitidine among frontline and relapsed/refractory AML patients who are venetoclax treatment naïve. 

The company intends to conduct two trials. The first, among relapsed/refractory patients, will initiate in 2H23. The second, among frontline patients, will initiate in 1H24. Aptevo anticipates that approximately 100 patients will participate between the two trials and that interim results will be available in late 2H24.

Price Action: APVO shares are down 25.40% at $1.06 on the last check Tuesday.